Hard drinking water does not protect against cardiovascular disease: new evidence from the British Regional Heart Study

Healthy eating behaviors may be associated with lower risk of premature coronary artery disease: A multi-center case-control study

BACKGROUND

Despite some evidence on individual eating habits in relation to cardiovascular disease, little is known about the combination of common eating habits in relation to premature coronary artery disease (PCAD).

OBJECTIVE

We investigated the association between a combined eating habits score (EHS) and PCAD risk.

METHODS

In this case-control study, 2022 patients with PCAD and 1063 healthy control were recruited. Women aged between 18 and 70 and men aged between 18 and 60 years were eligible. PCAD was defined as 75% or more stenosis in a single coronary artery disease or at least 50% in the left main coronary artery. Eating habits were assessed through interview and higher scores represent healthier behaviors.

RESULTS

Participants in the fourth quartile of EHS had 22% lower risk of PCAD than those in the first quartile (95% CI: 0.61, 0.99; P = 0.024). Not adding salt at the table (OR = 0.80, 95% CI: 0.66, 0.97; P = 0.023), low-salt meals (OR = 0.75, 95% CI: 0.57, 0.99; P = 0.022), and slow eating (OR = 0.42, 95% CI: 0.24, 0.71; P < 0.001) were associated with lower risk of PCAD while more water drinking (OR = 1.56, 95% CI: 1.07, 2.27; P = 0.013), and increased meal frequency (OR = 1.85, 95% CI: 1.09, 3.13; P = 0.025) were linked with increased risk of PCAD.

CONCLUSION

Healthy eating behaviors score, particularly low salt intake and slow eating were associated with lower risk of PCAD. However, higher meal frequency and more water drinking were associated with increased risk of PCAD. Well-designed prospective cohort studies are required.

Domestic water hardness, genetic risk, and distinct phenotypes of cardiovascular disease

AIMS

The study aimed to investigate the association between domestic water hardness and the incidence of AF and the interaction effects between water hardness and genetic susceptibility to incident AF risk. As a secondary objective, its associations with incident heart failure (HF), coronary heart disease (CHD), and stroke were measured.

METHODS

The UK Biobank is a prospective cohort study comprising over 500,000 participants recruited in the United Kingdom between 2006 and 2010, aged 37 to 73 years. A total of 447,950 participants did not have prevalent AF, and 423,946 participants who were free of HF, CHD, and stroke at baseline were included. Water hardness was assessed by CaCO3 concentration. The genetic risk score for AF was based on the standard polygenic risk score. Cox proportional hazards regression models and restricted cubic spline (RCS) analysis were conducted.

RESULTS

During a median follow-up of 13.74 years, 30,726 (6.86%) individuals were diagnosed with AF for the first time. Compared with those with water hardness ≤ 60 mg/L, individuals with domestic water hardness 121-180 mg/L had a 17% lower risk of developing AF (HR 0.83, 95% CI 0.79-0.87), but water hardness of 61-120 mg/L and > 180 mg/L was associated with a higher risk of incident AF (both 1.04, 1.01-1.07). A non-linear relationship between water hardness and incident AF (P for non-linear = 0.001) was found. Individuals with water hardness 121-180 mg/L were also significantly associated with a lower risk of incident HF (HR 0.82, 95% CI 0.75-0.89), CHD (HR 0.80, 95% CI 0.76-0.84) and stroke (HR 0.88, 95% CI 0.81-0.95). There were no significant interaction effects between water hardness level and genetic susceptibility to AF, HF, CHD, and stroke risk (all P for interaction > 0.05).

CONCLUSION

Potential U-shaped associations between domestic water hardness and incident AF across varying levels of genetic risk were found. Hard water (121-180 mg/L) may offer the most benefits compared to soft water when considering overall cardiovascular health, including AF, HF, CHD, and stroke.

The Relationship between Mortality from Cardiovascular Diseases and Total Drinking Water Hardness: Systematic Review with Meta-Analysis

BACKGROUND

Interest in water chemical activity, its content, and its impact on human health has greatly increased throughout the last decade. Some studies suggest that drinking water with high hardness may have preventative effects on cardiovascular diseases. This study aims to investigate the association between drinking water hardness and cardiovascular disease (CVD) mortality.

METHODS

The study selection process was designed to find the association between drinking water hardness and CVDs mortality. The search included both qualitative and quantitative research and was performed in three databases: Web of Science (Clarivate Analytics, Ann Arbor, MI, USA), PubMed (National Institute of Health, Bethesda, MA, USA), and Scopus (Elsevier, RELX Group plc, London, UK). The project was registered in the International Prospective Register of Systematic Reviews (PROSPERO), registration number: CRD42020213102.

RESULTS

Seventeen studies out of a total of twenty-five studies qualitatively analyzed indicated a significant relation between total water hardness and protection from CVD mortality. The quantitative analysis concluded that high drinking water hardness has a significantly lowering effect on mortality from CVDs, however, the heterogeneity was high.

CONCLUSIONS

This systematic literature review shows that total water hardness could affect CVD prevention and mortality. Due to the many confounding factors in the studies, more research is needed.

The effect of living environmental factors on cardiovascular diseases in Chinese adults: results from a cross-sectional and longitudinal study

AIMS

This study aimed to investigate the association between multiple living environmental factors and cardiovascular diseases (CVDs).

METHODS AND RESULTS

This study was conducted on the China Health and Retirement Longitudinal Study (CHARLS), with 12 489 subjects in the cross-sectional study and 7932 subjects in the 7-year follow-up. Living environmental factors included ambient fine particulate matter (PM2.5), indoor fuel use, tap water use, and residence type. Logistic regression and Cox proportional hazard regression models were applied to explore the association between living environmental risk factors and CVD events in a cross-sectional and a cohort analysis, respectively. Compared with subjects in the low-risk groups, those in the middle-risk (odd ratio [OR], 95% confidence interval [CI]: 1.203, 0.943-1.534) and high-risk groups (OR, 95% CI: 1.616, 1.259-2.074) showed increased risks of CVD prevalence when considering the combined effects of their living environment. During the follow-up, similar associations were observed (hazard ratio [HR], 1.541, 95% CI [1.142-2.080] for the high-risk group; HR 1.296, 95% CI [0.968-1.736] for the middle-risk group); P for trend = 0.003).

CONCLUSION

An overall poor living environmental quality is a potential risk factor for CVD. Future studies should focus more on the effects of exposure to multiple factors.

Design, Scale-Up, and Construction of Drinking Water Recarbonization Fluidized Bed Reactor System

The lack of calcium and magnesium in drinking water affects people’s health, especially cardiovascular and oncologic diseases, and causes corrosion problems. The aim of this paper is to present the methodology of the design, scale-up, and construction of a fluidized bed reactor (FBR) system for drinking water recarbonization with biogenic elements in real conditions. Half-calcined dolomite (HCD) in combination with CO2 was identified as a suitable source of Mg2+ and Ca2+. The experimental results confirmed that an FBR reactor with a water tank is an efficient system for Mg and Ca2+ ion concentrate production. The main process parameters and dimensions of the equipment were determined based on the experimental data and the data obtained showed that the system can be used in real conditions to produce Mg2+ and Ca2+ ions concentrate, which is mixed with soft water in required proportions. The FBR with an internal diameter of 0.16 m and a total height of 3.7 m was designed. The proposed methodology of the recarbonization process design was used in a further system scale-up for a ten times larger capacity. Long-term experiments indicate that the HCD recarbonization process is robust and can return to the steady state even after significant changes in the process parameters for providing the desired concentration of Mg2+ and Ca2+ ions in drinking water.

Calcium and magnesium in drinking water and risk of myocardial infarction and stroke-a population-based cohort study

BACKGROUND

The implication of calcium and magnesium in drinking water for cardiovascular disease is unclear.

OBJECTIVES

To assess the association of the concentration of calcium and magnesium in drinking water with incidence of myocardial infarction and stroke, accounting for dietary mineral intake.

METHODS

We linked drinking water monitoring data to residential information of 26,733 women from the population-based Swedish Mammography Cohort, who completed a 96-item FFQ at baseline. Drinking water was categorized into low (magnesium <10 mg/L and calcium <50 mg/L) or high (magnesium ≥10 mg/L or calcium ≥50 mg/L) mineral concentration. Incident cases of myocardial infarction and stroke types were ascertained 1998-2019 using the National Patient Register.

RESULTS

The mean ± SD concentration of calcium and magnesium in drinking water was 29 ± 7 mg/L and 5 ± 1 mg/L in the low-exposed area and 52 ± 20 mg/L and 10 ± 3 mg/L in the high-exposed area, respectively. During 16 years of follow-up, we ascertained 2023, 2279, and 452 cases of myocardial infarction, ischemic stroke, and hemorrhagic stroke, respectively. High drinking water calcium and magnesium was associated with lower risk of ischemic and hemorrhagic stroke HRs of 0.87 (95% CI: 0.80, 0.95) and 0.78 (95% CI: 0.65, 0.95), whereas the HR for myocardial infarction was 0.93 (95% CI: 0.85, 1.02). In separate analyses, only drinking water magnesium, not calcium, remained associated with ischemic stroke (HR: 0.69; 95% CI: 0.54, 0.88).

CONCLUSIONS

Drinking water with a high concentration of calcium and magnesium, particularly magnesium, may lower the risk of stroke in postmenopausal women.

The Risk of CVDs from Desalinated Seawater: A Nested Case-Control Study

The aim of this paper was to assess the association between desalinated seawater and cardiovascular diseases (CVDs). We conducted a nested case-control prospective study on a cohort of 7806 subjects who live on an island of China that lacks fresh water. From this cohort, we identified 140 paired CVD cases and matched controls by sex and age during the same period. Questionnaires were used in order to investigate basic sociodemographic information and risk factors for CVDs, and urine samples were collected to measure calcium and magnesium levels. Using these data we developed and tested both univariate and multivariate logistic regression models. We observed no significant differences in risk of CVDs between groups with desalinated seawater and fresh water intake. From multivariate logistic regression, we found that obesity (OR = 5.38, 95% CI: 1.05–27.45), physical activity (OR = 0.35, 95% CI: 0.16–0.75), hypertension (OR = 3.61, 95% CI: 1.58–8.25), alcohol consumption (OR = 2.57, 95% CI: 1.02–6.47), and irritability (OR = 4.30, 95% CI: 1.93–9.60) were associated with an increased risk of CVD. In this population, we found no association between desalinated seawater intake and CVDs; the incidence of CVDs was primarily related to lifestyle.

Association between magnesium in drinking water and atrial fibrillation incidence: a nationwide population-based cohort study, 2002-2015

BACKGROUND

Atrial fibrillation (AF) is a common heart rhythm disorder and a risk factor of adverse cardiovascular diseases. Established causes do not fully explain the risk of AF and unexplained risk factors might be related to the environment, e.g. magnesium in drinking water. Low magnesium levels in drinking water might be associated with higher risk of cardiovascular diseases including AF. With detailed individual data from nationwide registries and long-term magnesium exposure time series, we had a unique opportunity to investigate the association between magnesium in drinking water and AF.

OBJECTIVE

We evaluated the association between magnesium concentration in drinking water and AF risk.

METHODS

A nationwide register-based cohort study (2002-2015) was used including individuals aged ≥30 years. Addresses were linked with water supply areas (n = 2418) to obtain time-varying drinking water magnesium exposure at each address. Five exposure groups were defined based on a 5-year rolling time-weighted average magnesium concentration. AF incidence rate ratios (IRRs) between exposure groups were calculated using a Poisson regression of incidence rates, adjusted for sex, age, and socioeconomic position. Robustness of results was investigated with different exposure definitions.

RESULTS

The study included 4,264,809 individuals (44,731,694 person-years) whereof 222,998 experienced an incident AF. Magnesium exposure ranged from 0.5 to 62.0 mg/L (mean = 13.9 mg/L). Estimated IRR (95% CI) compared to the referent exposure group (< 5 mg/L) was 0.98 (0.97-1.00) for the second lowest exposure group (5-10 mg/L), and 1.07 (1.05-1.08) for the two highest exposure groups (15-62 mg/L). Strongest positive associations were observed among those aged ≥80 years and with lowest education group. An inverse association was found among individuals with highest education group.

CONCLUSION

There might be a small beneficial effect on AF of an increase in magnesium level in drinking water up to 10 mg/L, though an overall positive association was observed. The unexpected positive association and different associations observed for subgroups suggest a potential influence of unaccounted factors, particularly in vulnerable populations. Future research on magnesium in drinking water and cardiovascular diseases needs to focus on contextual risk factors, especially those potentially correlating with magnesium in drinking water.

Calcium intake, calcium supplementation and cardiovascular disease and mortality in the British population: EPIC-norfolk prospective cohort study and meta-analysis

The role of dietary calcium in cardiovascular disease prevention is unclear. We aimed to determine the association between calcium intake and incident cardiovascular disease and mortality. Data were extracted from the European Prospective Investigation of Cancer, Norfolk (EPIC-Norfolk). Multivariable Cox regressions analysed associations between calcium intake (dietary and supplemental) and cardiovascular disease (myocardial infarction, stroke, heart failure, aortic stenosis, peripheral vascular disease) and mortality (cardiovascular and all-cause). The results of this study were pooled with those from published prospective cohort studies in a meta-analsyis, stratifying by average calcium intake using a 700 mg/day threshold. A total of 17,968 participants aged 40-79 years were followed up for a median of 20.36 years (20.32-20.38). Compared to the first quintile of calcium intake (< 770 mg/day), intakes between 771 and 926 mg/day (second quintile) and 1074-1254 mg/day (fourth quintile) were associated with reduced all-cause mortality (HR 0.91 (0.83-0.99) and 0.85 (0.77-0.93), respectively) and cardiovascular mortality [HR 0.95 (0.87-1.04) and 0.93 (0.83-1.04)]. Compared to the first quintile of calcium intake, second, third, fourth, but not fifth quintiles were associated with fewer incident strokes: respective HR 0.84 (0.72-0.97), 0.83 (0.71-0.97), 0.78 (0.66-0.92) and 0.95 (0.78-1.15). The meta-analysis results suggest that high levels of calcium intake were associated with decreased all-cause mortality, but not cardiovascular mortality, regardless of average calcium intake. Calcium supplementation was associated with cardiovascular and all-cause mortality amongst women, but not men. Moderate dietary calcium intake may protect against cardiovascular and all-cause mortality and incident stroke. Calcium supplementation may reduce mortality in women.

Environmental heavy metals and cardiovascular diseases: Status and future direction

Cardiovascular disease (CVD) and environmental degradation are leading global health problems of our time. Recent studies have linked exposure to heavy metals to the risks of CVD and diabetes, particularly in populations from low- and middle-income countries, where concomitant rapid development occurs. In this review, we 1) assessed the totality, quantity, and consistency of the available epidemiological studies, linking heavy metal exposures to the risk of CVD (including stroke and coronary heart disease); 2) discussed the potential biological mechanisms underlying some tantalizing observations in humans; and 3) identified gaps in our knowledge base that must be investigated in future work. An accumulating body of evidence from both experimental and observational studies implicates exposure to heavy metals, in a dose-response manner, in the increased risk of CVD. The limitations of most existing studies include insufficient statistical power, lack of comprehensive assessment of exposure, and cross-sectional design. Given the widespread exposure to heavy metals, an urgent need has emerged to investigate these putative associations of environmental exposures, either independently or jointly, with incident CVD outcomes prospectively in well-characterized cohorts of diverse populations, and to determine potential strategies to prevent and control the impacts of heavy metal exposure on the cardiometabolic health outcomes of individuals and populations.

Hard Water, More Elastic Arteries: A Case Study from Krupina District, Slovakia

The protective role of hard drinking water against cardiovascular diseases is well documented by numerous studies. This article describes the impact of Ca and Mg contents in the drinking water with different water hardness on the cardiovascular system (arterial stiffness, arterial age) of residents of the Krupina district, the Slovak Republic. The research was based on the measurements of arterial stiffness, including the measurements of aortic pulse wave velocity (PWVao) and the calculation of the arterial age of the residents. In total, 144 randomly selected residents were included in measurements, divided into the two groups according to Ca and Mg contents in drinking water (water hardness). The first group was supplied with soft drinking water (total dissolved solids (TDS): 200-300 mg·L^-1, Ca: 20-25 mg·L^-1, Mg: 5-10 mg·L^-1). The second group of residents was supplied with harder drinking water (TDS: 500-600 mg·L^-1, Ca: 80-90 mg·L^-1, Mg: 25-30 mg·L^-1). Differences in arterial stiffness between the two groups of respondents were documented. Higher arterial stiffness (low flexibility of arteries) was determined for a group of residents supplied with soft drinking water. This was reflected in higher PWVao levels, higher number of pathological cases (PWVao > 10 m·s^-1), and arterial age of respondents compared to their actual age. The "absolute" difference between the arterial and actual age between the two evaluated groups of residents (soft vs. harder water) was nearly 5 years on average. The higher arterial stiffness and age of residents that consumed soft drinking water indicate the health significance of lower contents of Ca and Mg in drinking water as an environmental risk factor of cardiovascular diseases. Measuring arterial stiffness of residents in the areas supplied with soft drinking water can be used as a non-invasive approach in the prevention of cardiovascular risks.

Association between exposure to desalinated sea water and ischemic heart disease, diabetes mellitus and colorectal cancer; A population-based study in Israel

BACKGROUND

Drinking water (DW) is an important dietary source of magnesium. Recently, Israel has increased its use of desalinated seawater (DSW) as DW country-wide. Its negligible magnesium content, however, raises concern that consumption of DSW may be associated with hypomagnesemia and increase the risk of ischemic heart disease (IHD), diabetes mellitus (DM), and colorectal cancer (CRC).

OBJECTIVES

We tested whether there was a change in incidence of negative health outcomes (IHD, DM, and CRC) following the introduction of DSW supply in a population-based ecologic study in Israel.

METHODS

A historical prospective analysis was applied to members aged 25-76 during 2004-2013 of Clalit Health Services (Clalit), the largest healthcare provider in Israel, using its electronic medical record database. Multivariable analyses were adjusted for age, sex, socioeconomic status, smoking status, and body mass index.

RESULTS

An increased odds ratio was found for IHD (0.96, 95% CI 0.93-0.99 at baseline and 1.06, 95% CI 1.02-1.11 at the end of the follow-up period), but no time trend was observed.

CONCLUSIONS

We found that the risk for IHD increased during the study period. The risks for DM and CRC were unchanged. Long term studies are needed for assessing the risk for CRC due to the long latency. The higher risk for IHD has practical public health implications and raise the need to add magnesium to DSW.

Cardiovascular diseases and hard drinking waters: implications from a systematic review with meta-analysis of case-control studies

This systematic review with meta-analysis, performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines, aims at evaluating the potential correlation between magnesium and calcium concentration in drinking waters and the risk of cardiovascular diseases (CVD), which impose a considerable burden in high-income countries. Included studies were of the case-control studies type. From an initial list of 643 potentially eligible articles, seven studies were finally retained in the quantitative analysis. Since each one of them assessed different ion concentrations, subjects exposed to the highest concentration versus those exposed to the lowest concentration were compared. By including an overall figure of 44,000 subjects, the result suggests a protective effect of the ions on CVD prevention, with an effect-size (ES) of 0.82 (95% confidence interval CI = [0.70-0.95], p-value = 0.008) for calcium, and ES = 0.75 (95% CI = [0.66-0.86], p-value = 0.000) for magnesium. Hard water consumption seems to be protective against CVD. However, the high heterogeneity (I² = 75.24, p-value = 0.001 for calcium; I² = 72.96, p-value = 0.0024 for magnesium) and the existence of publication bias limits the robustness and generalizability of these findings. Further high-quality studies are needed to reproduce and confirm these results.

Desalinated seawater supply and all-cause mortality in hospitalized acute myocardial infarction patients from the Acute Coronary Syndrome Israeli Survey 2002-2013

BACKGROUND

Consuming desalinated seawater (DSW) as drinking water (DW) may reduce magnesium in water intake causing hypomagnesemia and adverse cardiovascular effects.

METHODS

We evaluated 30-day and 1-year all-cause mortality of acute myocardial infarction (AMI) patients enrolled in the biannual Acute Coronary Syndrome Israeli Survey (ACSIS) during 2002-2013. Patients (n=4678) were divided into 2 groups: those living in regions supplied by DSW (n=1600, 34.2%) and non-DSW (n=3078, 65.8%). Data were compared between an early period [2002-2006 surveys (n=2531) - before desalination] and a late period [2008-2013 surveys (n=2147) - during desalination].

RESULTS

Thirty-day all-cause-mortality was significantly higher in the late period in patients from the DSW regions compared with those from the non-DSW regions (HR=2.35 CI 95% 1.33-4.15, P<0.001) while in the early period there was no significant difference (HR=1.37 CI 95% 0.9-2, P=0.14). Likewise, there was a significantly higher 1-year all-cause mortality in the late period in patients from DSW regions compared with those from the non-DSW regions (HR=1.87 CI 95% 1.32-2.63, P<0.0001), while in the early period there was no significant difference (HR=1.17 CI 95% 0.9-1.5, P=0.22). Admission serum magnesium level (M±SD) in the DSW regions (n=130) was 1.94±0.24mg/dL compared with 2.08±0.27mg/dL in 81 patients in the non-DSW (P<0.0001).

CONCLUSIONS

Higher 30-day and 1-year all-cause mortality in AMI patients, found in the DSW regions may be attributed to reduced magnesium intake secondary to DSW consumption.

The UK geochemical environment and cardiovascular diseases: magnesium in food and water

Cardiovascular diseases (CVDs) contribute approximately one-third to noncommunicable diseases in the UK. The central role of magnesium in CVDs (enzyme activity, cardiac signalling, etc.) is well established. Mortality and morbidity rates for CVDs may be inversely related to water hardness, suggesting a role for environmental magnesium. Published official and quasi-official data sources were evaluated to establish a model magnesium intake for a representative adult: standardised reference individual (SRI), standardised reference male (SRM) or standardised reference female (SRF). For typical dietary constituents, only tap water is probably locally derived and bottled water may not be. Fruits and vegetables are imported from many countries, while meat, dairy and cereal products represent a composite of UK source areas. Alcoholic beverages provide magnesium, there is doubt about its absorptive efficiency, and they are not locally derived. A simple model was devised to examine the effect of varying dietary contributions to total daily intake of magnesium. Omitting tap or bottled water, the combined intake, solid food plus alcoholic beverages, is 10.57 mmol Mg (84.5 % RNI) for the SRM and for the SRF, 8.10 mmol Mg (71.7 % RNI). Consumers drinking water derived from reservoirs or rivers, or supplementing it with the purest bottled water, improve their magnesium intake only slightly compared with water containing no magnesium. Choosing bottled water with high magnesium content when the public supply derives from rivers or reservoirs partially satisfies magnesium needs. Real improvement in SRI magnesium nutrition is seen only where water is hard. However, this conclusion cannot be validated until new measurement technologies for body magnesium become available.

Serum calcium levels are not associated with coronary heart disease

Background

Numerous studies have reported that low calcium intake is related to a higher prevalence of cardiovascular disease. However, the relationship between serum calcium and coronary heart disease is unclear. The purpose of this study was to compare serum calcium levels in patients with coronary heart disease and those in healthy individuals.

Methods

This retrospective, case-control study conducted in the People’s Republic of China comprised 380 cases and 379 controls. Serum calcium levels, blood lipids, and anthropometric measurements were measured in both groups. The Student’s unpaired t-test or Chi-square test was used to compare differences between cases and controls. Pearson’s partial correlation coefficient was used to determine the association between serum calcium, blood lipids, and blood pressure in both groups.

Results

Our results indicate that the average level of serum calcium in cases was higher than in controls. Serum calcium levels showed no correlation with any parameter except for triglycerides in either group.

Conclusion

Overall, these data suggest that serum calcium has no influence on coronary heart disease or triglyceride levels in the general population.

The relationship between serum calcium level, blood lipids, and blood pressure in hypertensive and normotensive subjects who come from a normal university in east of China

Previous studies revealed that low calcium intake is related to high prevalence of cardiovascular diseases such as hypertension. However, the relationship between serum calcium and blood pressure was unclear. The prevalence of hypertension is high in China. Thus, the aim of this study was to evaluate the serum calcium level between hypertensive and normotensive groups and to investigate the correlation between serum calcium, blood pressure, and blood lipid parameters. A total of 1,135 adult subjects participated in this study and were divide into two study groups: a hypertensive group (n = 316) who had 140 mmHg or higher in systolic blood pressure (SBP) or 90 mmHg or higher in diastolic blood pressure (DBP) and an age- and sex-matched normotensive group (n = 819, 120 mmHg or less SBP and 80 mmHg or less DBP). Our results indicate a significant trend for men (60 years old or older) in the direction of decreasing blood pressure with increasing serum calcium level, but no trend for women was indicated. In the normotensive group, a significant positive correlation was found between DBP and total cholesterol (P < 0.01) and triglyceride (P < 0.01), Likewise, triglyceride was positively correlated with SBP (P < 0.01). Overall, these data suggest that serum calcium may have an influence in the blood pressure of older male subjects with hypertension and in blood lipid profiles of normotensive subjects.

Designing water supplies: Optimizing drinking water composition for maximum economic benefit

It is possible to optimize drinking water composition based on a valuation of the impacts of changed water quality. This paper introduces a method for assessing the potential for designing an optimum drinking water composition by the use of membrane desalination and remineralization. The method includes modeling of possible water quality blends and an evaluation of corrosion indices. Based on concentration-response relationships a range of impacts on public health, material lifetimes and consumption of soap have been valued for Perth, Western Australia and Copenhagen, Denmark. In addition to water quality aspects, costs of water production, fresh water abstraction and CO(2)-emissions are integrated into a holistic economic assessment of the optimum share of desalinated water in water supplies. Results show that carefully designed desalination post-treatment can have net benefits up to €0.3 ± 0.2 per delivered m(3) for Perth and €0.4(±0.2) for Copenhagen. Costs of remineralization and green house gas emission mitigation are minor when compared to the potential benefits of an optimum water composition. Finally, a set of optimum water quality criteria is proposed for the guidance of water supply planning and management.

High adiponectin and increased risk of cardiovascular disease and mortality in asymptomatic older men: does NT-proBNP help to explain this association?

BACKGROUND

Raised adiponectin is associated with increased rather than decreased risk of cardiovascular disease (CVD) and mortality at older age. We examined whether N-terminal pro-brain natriuretic peptide (NT-proBNP), a marker of cardiac dysfunction, may help explain this relationship.

METHODS AND RESULTS

A prospective study of 2879 men aged 60–79 years with no history of CVD at baseline followed-up for a mean of 9 years during which there were 196 major coronary heart disease events (fatal and non-fatal myocardial infarction) and 667 deaths (including 225 CVD deaths), whereas adiponectin concentration was inversely associated with several conventional CVD risk factors; it was significantly and positively associated with NT-proBNP concentration. After adjustment for several vascular risk factors, including renal function and muscle mass, relative risks associated with a top third versus bottom third comparison of adiponectin concentration were 1.51 (1.02–2.23) for coronary heart disease, 1.67 (1.15–2.41) for CVD mortality and 1.41 (1.13–1.95) for all cause mortality. Upon further adjustment for NT-proBNP, these relative risks attenuated to 1.31 (0.88–1.94), 1.31 (0.90–1.91) and 1.26 (1.01–1.59), respectively.

CONCLUSION

We show for the first time that concomitantly elevated NT-proBNP concentration, at least, partially explains the apparently positive relationship between adiponectin concentration and risk of CVD and mortality in asymptomatic elderly men.

Relationship between tap water hardness, magnesium, and calcium concentration and mortality due to ischemic heart disease or stroke in The Netherlands

BACKGROUND

Conflicting results on the relationship between the hardness of drinking water and mortality related to ischemic heart disease (IHD) or stroke have been reported.

OBJECTIVES

We investigated the possible association between tap water calcium or magnesium concentration and total hardness and IHD mortality or stroke mortality.

METHODS

In 1986, a cohort of 120,852 men and women aged 5569 years provided detailed information on dietary and other lifestyle habits. Follow-up for mortality until 1996 was established by linking data from the Central Bureau of Genealogy and Statistics Netherlands. We calculated tap water hardness for each postal code using information obtained from all pumping stations in the Netherlands. Tap water hardness was categorized as soft [< 1.5 mmol/L calcium carbonate (CaCO3)], medium hard (1.62.0 mmol/L CaCO3), and hard (> 2.0 mmol/L CaCO3). The multivariate case-cohort analysis was based on 1,944 IHD mortality and 779 stroke mortality cases and 4,114 subcohort members.

RESULTS

For both men and women, we observed no relationship between tap water hardness and IHD mortality [hard vs. soft water: hazard ratio (HR) = 1.03; 95% confidence interval (CI), 0.851.28 for men and HR = 0.93; 95% CI, 0.711.21 for women) and stroke mortality (hard vs. soft water HR = 0.90; 95% CI, 0.661.21 and HR = 0.86; 95% CI, 0.621.20, respectively). For men with the 20% lowest dietary magnesium intake, an inverse association was observed between tap water magnesium intake and stroke mortality (HR per 1 mg/L intake = 0.75; 95% CI, 0.610.91), whereas for women with the 20% lowest dietary magnesium intake, the opposite was observed.

CONCLUSIONS

We found no evidence for an overall significant association between tap water hardness, magnesium or calcium concentrations, and IHD mortality or stroke mortality. More research is needed to investigate the effect of tap water magnesium on IHD mortality or stroke mortality in subjects with low dietary magnesium intake.

Geographic life environments and coronary heart disease: a literature review, theoretical contributions, methodological updates, and a research agenda

A growing literature investigates associations between neighborhood social environments and coronary heart disease (CHD). After reviewing the literature, we present a theoretical model of the mechanisms through which geographic life environments may influence CHD, focusing particularly on the social-interactional environment. We suggest that, in addition to the common notions of social cohesion or fragmentation and social disorder, eco-epidemiologists should consider neighborhood identities and stigmatization processes. We posit that neighborhood social interactions affect the wide set of affective, cognitive, and relational experiences individuals have in their neighborhoods, which in turn influence the psycho-cognitive antecedents of behavior and in the end shape health behavior. Finally, we discuss key methodological challenges relevant to the advent of a new generation of neighborhood studies, including the operational definition of neighborhoods, non-residential environments, ecometric measurement, model specification strategies, mediational models, selection processes and notions of empirical/structural confounding, and the relevance of observational versus interventional studies.